Not much of a diversion, closer to a false flag operation, followed by an interception. Absolutely unfathomable.
At the moment, we lack a lot of crucial information, particularly as it pertains to the timeline of things happening on the flight. When did the threats of a bomb aboard start? Immediately after entering BY airspace? To my knowledge, we are currently mostly operating on Twitter posts. With hindsight, one would take the AC over Polish (NATO) airspace right then and there, but who here could honestly make that call from a flight deck in that situation. At the time the AC turns for Minsk, they would have been closer to EYVI...so if we assume that this is the point where the crew starts taking the threat seriously, that would be your logical destination...however, a Fulcrum on your wing will surely dissuade you from just "sending it" at that point.
What matters now is that passengers and crew are returned unharmed ASAP and that Belorussian airspace be avoided for the foreseeable future. A criminal and despicable act that needs to have consequences.